Persistent corneal epithelial defects and recurrent corneal erosions are serious clinical problems. Rational treatment of corneas with such defects requires an understanding of the basic cell biology of the two major cell processes which occur during the healing process. They are: movement of the corneal epithelial cell across the wound or abrasion and adhesion of the cells to their basement membrane. We plan to do a correlated ultrastructural, histochemical and biochemical study of the cytoplasmic filament systems which are involved in the movement of the corneal epithelial cells to cover wounds or abrasions. In addition to studying the role these filaments play in motility, we will begin to determine the role the 10 nm filament plays in cell adhesion within the hemidesmosome. We will determine the effects of drugs which retard and stimulate wound healing, on corneal epithelial cell filament systems. We will determine the role cell surface and basement membrane sugars play in cell movement and adhesion by employing lectins which are sugar specific ligands. These studies will give us information about the corneal epithelium and how it normally goes about healing a wound. Such understanding will then allow us to probe abnormally healing corneas to determine cell defects which lead to persistent epithelial defects and recurrent corneal erosions.